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Jan. 3, 1939. C M F, FRIDEN 2,142,892

CALCULATING MACHNE Original Filed Feb. 6, 1928 ll Sheets-Sheet l m :E lEnlw O zas NVENTOR BY Car/ M Eva/@f7 MA TTORNE Ys Jan. 3, 1939.

c. M. F. FRIDEN CALCULATING MACHINE 1928 ll Sheets-Sheet 2 Original Filed Feb. 6

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Jan. 3, 1939- c; M. F. FRIDEN `CALGU'LATING MACHINE 1928 4 ll Sheets-Sheet 5 Original Filed Feb. 6

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CALCULATING MACHINE Original Filed Feb. 6, 1928 ll Sheets-Sheet 7 -..mln lmHh Jan. 3, 1939. c, M. F. FRIDEN CALCULATING MACH INE Original Filed Feb. 6, 1928 ll Sheets-Sheet 8 INVENTOR /flg /U/IMMINIMUM/HH] m4n... mUHJImH Jan. 3, 1939. c, M. F. FRIDEN GALCULATING MACHINE Original Filedv Feb. 6

, 1928 ll Sheets-Sheet 9 Jan. 3, 1939.

Original Filed Feb. 6, 1928 c. M. F. FRIDEN 2,142,892

CALCULATING MACHINE ll Sheets-Sheet lO INI 'E YTOR Y Car( M f.' Hide/1 /Q .4 TTORNE Ys Jan. 3, 1939. c. M. F. FRIDEN CALCULATING MACH INE original Fiied Feb. e, 1928 ll Sheets-Sheet l l F'lE `I E AC TUA TOR Patented jan. 3, 193@ encourus@ MACHINE cui M. F. miden, Osanna, cam., um to Merchant Calculating Machine Company, Emeryville, Calif., a corporation of California 5 calculations. is set to perform problems in division, for holding 5 'Ihe calculating machine comprises s. rotary acthe motor circuit closed during the time that the tuator and a plurality of keys for introducing actuator is stopped. f values into the actuator. The depression of a .The invention possesses other advantageous key introduces a value corresponding to the nufeatures. 80m@ 0f which With the foregoing Will be lo meral on the key, into the rotatable actuator set forth at length in the tollowingdescription, lo -and rotation of the actuator serves to transfer Where I shall outline in full that form of my. these values into the counter r register, t0 effect invention which I have Selected fOr illustration in the calculating operation. The values introthe drawings accompanying and forming Dart 0f duced into the actuator are transmitted, on rothe present specification.

i tation of the actuator in either direction to the In Said drawings, I have Shown one form of is figure discs oi.' the counting mechanism, which, mehnim @mbOdying my invention as it is em for thepurpose of making direct action oi the bodied in e. Merchant calculating machine, but it selected values on the iigure discs of highest .is to he understood that I do not limit myself to value possible, is disposed in parallel displace such form, since the invention, as set forth in able relation to the axis or the actuator. The the claims, may be embodied in a plurality of 2o counting mechanism comprises a series oi` nuforms. meral wheels which are mounted on a carriage Referring to said drawings: which is displacesble transversely of the calcon Fis.' i is a top or plan view oi? a portion or a latins; machine, with respect to the actuator. calculating machine embodying my invention,

The present invention relates particularly to the casing being removed and several perte being 25 means for controlling the operation of the mashown in section, to better illustrate' the conchinc in the performance oi' problems in division. struction. These means include devices operative to correct Fis. 2 is a vertical, longitudinal section through an overdraft registration in one position.- of the a calculating machine embodying my invention,

carriage, then shift the carriage, then correct the showing the positive and negative operation keys 3o overdraft registration in the shifted position and and the drive control mechanism which is conso on until the machine is automatically brought trolled thereby. to a stop when the carriage has been shifted to Fig. 3 is a vertical, longitudinal section through its limit position. the calculating machine, showing the means for An object ci the invention is to provide a calsetting the machine for 'the performance oi' 3;,

culating machine adapted to perform the four problems in division. rule calculations, with means whereby the ma- Fig. 4 is a detail showing the motor switch conchine may be set to perform problems in division trol lever 'in open switch, position, and Fig, 5 only. is a similar view showing the control lever in 40 Another object of the invention is to provide closed switch position. 4o a Calculating machine having means .for auto- Ilig. 61s a vertical, longitudinal section through matically Shifting the Carriage, Which means iS the calculating machine showing a portion of the disabled except when the machine is Set to persetting mechanism for setting the machine for form problems i!! diviin the performance of problems indivision and the 4t Another object of the invention 1S t0 provide clutch for eonironing the shifting of the carriage. 45

a calculating machine, which when set to per- 5:11,;7 1s 9, detail of the carriage shifting control form problems in division, operates on the occlutch @S1011 0f @In overdraft regtmt'on m the nu" Figisalongltudinal, vertical section through meral wheels, to correct the overdraft, stop the 9, calculating machine embodying my invention,

actuator ,and Shift the @alliage t0 the next Posishowlng the positive and negative operation keys, 50 tion, start the actuator again in a subtractive the qugueni; register and the means for Operating direction until an overdraft occurs correct the auch register, overdraft, again stop the actuator and shift the Fig. 9 is a detail of the reversing mechanism carriage and continue such operations to disclose interposed between the motor and the actuator.

the proper, complete quotient fig-ure. Fig. 10 is a rear elevation of a calculating ma- Sev Application February s, 192s, serial No. 252,175 Renewed February 15. 1938 13 Claims.

The invention relates to calculating machines oi' the motor driven type and particularly to the means for controlling the actuation of tite machine in performing problems in the four rule (Cl. 23H3) Another object o! the invention is to provide a calculating machine, having a driving motor which is normally stopped when the actuator is stopped. with means operative when the machine litt negative key is chine, parte thereof being broken away and other part being shown in section, to illustrate the construction of the machine.

Fig. ll. le a vertical transverse section through the calculating machine, showingthe carriage shifting echanism and the control mecha therefor. g

Y Fig. l2 is a vertical, transverse sectionlthrough the calculating mae, showing the control mechant which is operative to stop the' ma= chine after the carriage has reached its extreme left hand position Fig. i3 is a detail showing the means for releasing the menism which controls the stopping of the machine, after the carriage has reached its estreme left d position.

Fig. le is a vertical, longitudinal section through the rear portion of the machine, showina the actuator, the register, and the means operated hy a transitional carry of oneof the numeral wheels of the register to reverse the direction of rotation of the actuator.

Fig. l5 is a detail of one nuit of the actuator in association with two numeral wheels of the register.

Fig. it is a detail showing the means actuated by a transitional carry of the numeral wheels to control the reversal of the actuator.

Fig. i7 is a rear elevation of the switch in the motor circuit.

Fig. le is a diagratic representation of the motor. circuit.

Eig. l@ is a diagrammatic representation of the drive for the ous elements of the calculating machine.

The invention relates to motor driven calculating machines and particularly to the control mechanism for controlling the operation of the actuating means andthe motor and the movement of the carriage. `The machine is provided with positive and'negative operation keys, `depression of the positive key serving to cause rotation of the actuator in an additive direction and depression of the negative hey serving to cause rotationl of the actuator in a suiotractive direction. The positive key is used primarily in performing problems in addition and multiplication and the used primarily for performing problems in subtraction and division, although in short cut multiplication, the negative lsey is also employed. The present invention concerns itself chley with providing means for accomplishing the automatic solution of a problem in division. In such problems. the negative operation hey is employed. and means are provided for loclsing the positive operation key against action; when the machine is set to perform problems in division, so that the operator may not maire an error.- The negative operation key is associated with means which are edective only when the machine is set to perform problems in division, for automatically reversing the direction of rotation of the actuatorupon an overdraft registration of the numeral Wheels, to stop the actuator at the end of one cycle of such reversed move-f ment, so that the quotient register will show the true quotient ngure, to shift the carriage to its next position, to again rotate the actuator in a subtractive direction until an' overdraft registration occurs, to then automatically reverse the direction of rotationof the actuator, to stop the actuator at the end of one cycle of such reversed movement, to shift the carriage to its next posiriage reaches thalimit of its movement, at which figure produced.

The present machine includes a suitable frame,

within which the various instrumentalities of the calculating machine are arranged. Many of these lnstrumentalities including the speelde construction of the actuator, the connections between the numeral lteys and the actuator, the automatic multiplication mechanism and other features of the machine are fully disclosed in my Unid States Patent No. 1,643,710 of September 27, 1927, to which reference is hereby made for a complete disclosure of those features of the calculating machine which are not speeieally disclosed in this application. The calculating machines include a reversible, rotary actuator 2 comprise ing a series of units into which values are introduced by the depression of keys. Each unit is also lprovided with tens carrying pins for transferring values to the numeral wheels of the count= -ing mechanism of the nent highest order. hach unit is provided with tt-vo tens carrying pins and the two series of pins on the actuator are ma ranged in diverging spirals. @ne series of pins is eective in carrying tens during an additive or forward rotation of the actuator and the other series of pins is effective in carrying tens during a substractive or reverse rotation of the actuator. The values introduced into the actuator by the depression of keys are transferred, upon rotation of the actuator in either direction, to the numeral wheels i3 of the counting mechanism, or counting register as it is generally known, thru the intermediate gears il. The product resister, together with its associated intermediate gears and trans= fer levers is arranged on a transversely movable carriage 5, which is guided in suite-.hie tracirvays in the frame, so that the carriage may se moved to establish cooperation between desired numeral wheel and any desired unit of the actuating means, within the limits of movement of the carriage. Associatm with each counting wheel t is a transfer lever which is actuated upon movement of the numeral wheel, forwardly to of reversely from zero position, movement being referred to as a transitional carry. This movement of the transfer lever fi is enacted hy an associated toothed member 'l secured to the numeral wheel.

The actuator is driven by the motor ii and interposed between the motor and the actuator is a clutch for connecting and disconnecting the motor from the actuator, and a reversing nimhanism, whereby the direction of rotation of the `actuator may be reversed. lhs clutch, shown in lig. 2, embodies a driving shaft il, suitably connected to the motor shaft by means of the speed reduction gearing, es shown in his. l, and the driving shaft isprovlded on its end with a ratchet pinion l2, which rotates continuously with the motor. The motor is provided with a switch which is closed only during the time that the machine is functioning to perform a problem in calculation. Journalled on the driving shaft e and enclosing the ratchet pinion l2 is a clutch housing i3, within which is pivoted a dog id which is adapted to be moved into and out of engagement with the ratchet pinion i2, to connect and discon nect the pinion and the housing. The dog or pawl it is urged toward engagement with the pm- -ion i2 by the spring i5. The clutch housing i8 is provided on its periphery with an aperture i6 thru which a foot il on the end'of the pawl id extends when the patvl is in engagement with the pinion. -'Ihe patvl is disengaged from the on aisance by inward movement of the foot l1 and this is accomplished by means of the clutch control lever I3 which is provided on its end with a foot i3 which, when the lever I8 is released of itsrcstraint is moved into contact with the periphery of the housing I3 by the spring 2l, and, as the housing rotates, the foot I9, contacts' with the foot l1 and enters the aperture I6, thereby disengaging the clutch and locking the clutch housing. The clutch housing is so positioned with respect to the actuator that when the clutch housing is locked the actuator is locked in full cycle position.

Secured to the clutch housing i3 is a hollow stub shaft 23, which forms part of the reversing gearing. Journalled on the hollow shaft 23 are two gears 24 and 23 either of which may be dlrectly connected to the hollow shaft to rotate therewith. Each of the gears 24 and 2li is provided on its inner periphery with an interrupted ange 28, the two flanges being in contact, The hollow shaft 23 (Fig. 10) is provided with an aperture extending diametrically therethrough and disposed in the aperture is a cross pin 21 which is adapted to seat in the interruption oi' either4 of the flanges 23. (Fig. 9.) 'Ihe pin 21 is of less diameter than the depth of the iiange so that the pin may seat entirely within either flange. The pin is movable transversely, in the direction of the axis of the shaft 23, to bring it into engagement with either of the gears 24 or 25, and for this purpose, the pin 21 is secured to the rod 28 which extends outward from the end of the hollow shaft 23 and is suitably supported at its other end in the frame of the machine. The interruptions in the flanges 26 are somewhat wider than the diameter of the pin 2l to permit the pin to be shifted to reverse the direction of rotation of the actuator without bringing the actuator to a stop. Meshing with the gear 2d is an idler gear 3i which in turn meshes with a gear 3?. which is directly in mesh with the gear 2E. Therefore, the gear 32 is driven in one direction when the gear 24 is in engagement with the hollow shaft 23 and in the opposite direction when the gear is in engagement with the hollow shaft 2S. ,Secured to the shaft of the gear 32 is a gear 33 lying on the opposite side of the intermediate wall 3i and the gear 33 is connected to the gear 36 on the actuator shaft by the intermediate gear 35. Therefore, shifting of the pin 27 reverses the direction ci rotation oi the actuator.

Means are provided for either manually or automatically shifting the pin 21 to reverse the direction of rotation of the actuator. Secured to the shifting rod 28 is a collar 33 which is enclosed by the spring housing 33, between the end oi' which and the collar 33 there is inserted a compression spring 4i (Fig. 10) which holds the housing tightly against the collar. so that movement of the housing toward the right will effect movement of the rod 28 and permitting movement of the rod 23 to the right without moving the spring housing. In Fig. 10, the pin 21 is shown in engagement with the gear 24, thus producing reverse or subtractive drive of the actuator. Movement of the pin 21 to the right and into engagement with the gear 25 will cause forward rotation of the actuator. Engaging in a circumferential groove in the spring housing 39, is a fork 42 which is attached at its other end to the shifting rod 43 (Fig. 1) which is suitably journalled within the frame of the machine and which extends thru the hollow shaft carrying the transmission gear 44. By movement of the shifting rod 43which is manually operated, the pin 2i may be moved to cause forward or reverse drive of the actuator. The direction oil rotation of the actuator may be reversed manually by moving the fork 42 and is reversible automatically by movement of the rod 28. These two means oi accom-1. plishing the reversal of rotation oi the actuator will be set forth in full hereafter.

Manual operation'of the reversing gear is ci iected by the depression. and release ci the negative operation key 3l, which is preferably arranged on the keyboard of the machine. Pivoted within the machine is a bell crank lever 52 (Fig. 8) which is normally held in restrained position by the spring 53, and when the lever l2 is in such restrained position, the reversing mechanism is in position to cause forward or additive rotation of the actuator. One leg of the bell crank lever 52 underlies a pin 34 on the stem of the negative operation key 3i so that when the key 5l is depressed, the lever 52 is moved against the restraint of the spring B3. 'Ihe lever 32 is connected by means ofthe link 55 with a lever 33 having a sector shaped cam 61 which engages in a slot 58 in the projecting end of the rod 43. Depression of the negative operation key 5| therefore shifts the rod 23 to cause reverse rotation of the actuator. The above described operation occurs when the machine is set to perform problerns in addition, multiplication and subtraction. Means are provided for setting the machine to perform problems in division and this setting means is associated with the link 55 so that when the setting means is operated to place the machine in condition to perform problems in divi= sion, the link 55 is shifted, shifting the rod 43 to cause reverse rotation oi the actuator. The mechanism for accomplishing the setting of the machine for this purpose will be hereinafter described.

The machine is also provided with a positive operation key 6i depression or' which causes forward" rotation oi the actuator. The connection between? the motor and the actuator is controlled by the clutch, and the action ci the clutch is controlled by the lever iii which is normally heid in clutch disengaging position by the spring 2i. Means are provided whereby the depression oi either Trey di or key- 6i will rock the lever i@ to move it out oi engagement with the clutch housing i3 and permit engagement oi' the clutch. Pivoted within the frame of the machine is a bell crank lever 52 (Fig. 2) underlying a roller 8d on stein oi' the negative operation key iii and having a suhstantlally vertical arm 65 lying in front of a roller 66 carried by the frame S1 of the positive operation key lli. The frame 31 is mounted on levers 58 in such manner that depression of the positive operation key 5i causes forward movement of the roller 68 against the upright portion of the bell crank lever, thereby rocking auch lever. It will be seen from Figure 2 therefore, that depression of eitherkey 6i or key Si will cause counterclockwise rotation of the bell crank lever 62. Pivoted to the arm of the lever @2 is a bar 'll provided on its under side at its rear end with a notch 12 in which a pin 13 on the forward end oi the clutch control lever i8 is normally disposed. Therefore, reaward movement oi the bar 1! rocks the lever i8 about its pivot to move it out of engagement with the clutch housing. Release of either of the depressed keys Si or iii will cause the clutch lever i8 to again move into engagement with the clutch housing and other means are provided independent of the depressed lever iii to cause it to engage the clutch housing. This is'accomplished by raising the rear end of the bar iii to move the notch l2 from engagement" with the pin i8 as will be described hereinafter. The calculating machine is also provided with a register or counting mechanism usually known as the multiplier register or quotient register, for indicating directly the proper and correct multiplier or quotient. This register comprises a series of numeral wheels 'ib (Fig. 8) each numeral wheel being provided with an intermediate gear ld and a transfer lever lll. Means are provided for causing a single operation of a selected numeral wheel for each rotation of the actuator in either direction, and tens carrying means are provided so that the register will always show the correct iigure. The numeral wheels iii are actuated in time with the rotation of the actuator by the rotatable single toothed member, iti which is splined to the shaft l0 which is rotatable in time with the actuator.

The tens carrying device in the particular embodiment shown, comprises a drum Bi having two series of tens carrying pins S2 and 83 thereon, the Y pins in the two series being arranged in divergupon reverse rotation of the drum. The drum is secured to a shaft 8G journalled in the frame of the machine and the tens carrying pins d2 and G3 cooperate with the transfer lever il to transfer values to thel numeral wheels of the nent highest order. Means are provided for reversing the direction of rotation of the actuator. The drum 9i is provided with a reversing gear, similar to that heretofore described herein. and comprising the two gears 85 and 8b, either of which may be directly connected to the shaft 86 by the transversely movable pin @l (Fig. 10) which is secured to the rod 538 which is disposed within the hollow shaft till. The gear SEB is in mesh with the idler gear 8i and the gear de is in mesh with the gear 32.' Since the gears Si and 32 always rotate in` opposite directions, the gears 435 and @t will always rotate in opposite directions and the direction of rotation of the drum @i is determined by which of the gears ed or @t is secured to the shaft thereof. The rod titi (Fig. i0) extends to the end of the hollow shaft @il and projects slightly therefrom. The shaft d8 is urged toward the left by the spring te disposed in the bore of the hollow shaft and means are provided for exerting a pressure on the end of the `rod 98, to move it against the pressure of the spring. When the machine is set to perform problems in division, the parts are in the position shown in Figure 10, with the gear @E5 secured to the shaft fifi. When the machine is set to perform problems in multiplication and addition, the spring Gli positions the pin el in the recess in gear 85, connecting this gear with the hollow shaft dil. Therefore, the direction of rotation of the drum iii may be reversed with'respect to the direction of rotation ofthe actuator.

Secured to the opposite end of the drum shaft SQ is a gear 9i which ls connected, thru the intermediate gear s2 (Fig. 3) with the gear @8 secured to the end of the multiplier register actuating shaft i9. Thereforethe direction of rotationof the actuating member l is reversed simultaneously with the direction of rotation of the drum si. The actuating member it, is adjustable longitudinally of its shaft, so that it may be disposed in cooperative relation with the selected numeral wheels 'l5 and for this purpose amasar the gear is provided with a grooved collar which `is engaged by a shifting fork Qdwhich is medif di are reversed with respect to the direction of rotation of the actuator and means are provided for edecting this reversal of direction of rotation when the machine is set to perfo problems in division. Also. in performing problems in division, the actuator rotates in a reverse direction and means are provided for shifting the pin 2l to cause reverse vdirection of rotation of the actuator when the machine is set for performing problems in division. The means employed for setting the machine to perform problems in division operate to perform both of the above functions, together with other functions which will be described hereinafter.

Arranged at the side of the machine is a setting lever ed (Fig. 3) which, in its backward position, sets the machine for performing problems in addition, subtraction and multiplication, and which, in its forward position, sets the machine in condition for the automatic performance of problems in division. The lever 36 cooperates with a spring pressed latch plate Oi which serves to hold the lever in adjusted position. Pivoted to the lower end of the lever QG is a bar @ii which is pivoted at its rearward end to the lever 9s (Fig. 6) by means of the screw isi. The lever s@ and the lever @d lie on opposite sides of a partitioned wall and the connection screw itil extends thru a slot M32 in the partitioned wall. stud or boss its and is provided with a double cam extension or arm liiil, the cam iii@ serving to control the direction of rotation of the drum iii and the cam lil@ serving to control the operation of the division stop, as will be hereinafter described. The cam portion iii@ of the lever arm idd is operatively associated with the projecting end of the rod El@ (Fig. 10) and serves to control the longitudinal movement of the rod 83 and consequently the position of the transverse pin di. in Figure 10, the parts are shown in the position to set the machine to perform problems in division, the cam portion its being operative to hold the rod .dit depressed. Projecting laterally from the bar @d is a stud its (Fig. 3) which lies in front of the vertical leg its (Fig. 8) of the link 5b so that when the .lever @t is moved to its forward or.division position, the stud is@ .is moved backwards moving the link 55 backward and moving the cam ill to shift the shaft/(i3 (Fig. l.) which causes the fork i2 to position the pin 2l (Fig. 10) to cause reverse rotation of the actuator. Therefore, shifting the lever @t to its division position positions the main driving reverse gear to cause reverse rotation of the actuator and positions the reverse gear of the drum si so that the drum rotates in the opposite direction with respect to the direction of rotation of the actuator.

In machines of this character, when used in the perfomance of problems in division, the numeral wheels of the product register to the left of the wheels being operated upon by the actuator, change sign when an endeavor is made to divide the divisor into the dividend a greater whole number of times than is possible. Under such conditions, the numeral wheels registration The lever 9@ is journalled on a anism for stopping kthe machine. Division is accomplished by a reverserotation of the actuator and, when a condition oi'l overdraft registration existed and the machine had been brought to a stop, the positive operation key was then depressed to cause rotation of the actuator in a forward direction for one revolution to correct the overdraft registration. This correction of the overdraft registration by operation of the positive operation key, produced the proper number in the product register and the proper indication in the quotient register. In the present construction, the overdraft registration is utilized to eii'ect the automatic reversal of the direction of rotation` oi' the actuator, without stopping the actuator so that the actuator is then given a forward or additive rotation and is then brought to a stop at theend of the first cycle of forward rotation. This means, however, is disabled when the machine is set to perform problems in addition, multiplication and subtraction and is brought into operation only when the machine is set to perform problems in division. Therefore, this automatic reversal means does not function on the event of an overdraft registration during multiplication, which,r if not observed would resuit in the introduction of errors into the calculation. The shifting of the setting lever 98 to division position, also serves to enable the automatically operating means for reversing the direction of rotation of the actuator in the event of an overdraft registration and to stop the actuator at the end of its first cycle of forward rotation. Therefore, in performing problems in division, the operator merely depresses the negative operation key 5| andthe actuator rotates in a reverse direction until there is an overdraft registration and then the actuator is automatically reversed and stopped at the end of the iirst cycle of forward rotation. The carriage is then shifted to the next position and the division op eration continued until the actuator is again brought to a stop by virtue of an overdraft registration, after which the carriage is again shiftedA and the operation is repeated until there is no remainder left in the product register or until the product register carriage lreaches the end of its movement toward the left. Heretofore, the

movement of the carriage has been effected both by hand and by mechanism which is thrown into operation during the corrective or additive rotation of the actuator and, after the shifting of the carriage, the machine was brought to rest so that a further operation of the negative operation key was necessary to perform the next divisional operation step. In accordance with the present invention, the actuator is again started in rotation in a subtractive direction, as soon as the carriage has been shifted so that the operation of division which would result in a quotient containing a plurality of gures, is automatically accomplished by the single depression of the negative operation key.

Means are provided which are operative during the reverse or corrective rotation of the actuator, when the machine is set for performing problems in division, for reversing or changing to an additive rotation, the rotation of the actuator when an overdraft registration occurs, which overdraft is usually indicated by a change of sign of the numeral wheel of the next to the `a laterally shifting member. This other instrumentalities in shape of the bar does not otherwise enter into its highest order within the range of the actuator. This change of sign in a division operation is from zero' to nine. On this change ot sign, the toothed element 'l (Fig. 14) moves the transfer lever C backward. Pivoted on the stud Ill (Fig. 16) is a lever HB having a transversely extending arm which lies behind and in contact with the rear face of the transfer lever I at the left of the series being operated on. The arm is held in engagement with the transfer lever by the spring I8, so that when the transfer lever 8 is rocked backwardly at the time of an overdraft registration or transitional carry, the lever IIB is rocked onI its pivot. Secured to the lever H6 is a laterally shii'table arm I8 which is preferably provided with a slot |2| for receiving member is shifted to either of two positions, by the setting ofthe machine to perform the desired problem and in Figure 16, the arm H9 is shown in its division" position.

The arm H9 is shifted sidewise into and out of operative engagement with the reversing and stopping mechanism by means of the bar |22 (Fig. 10). This bar has a turned-down end which is disposed in the slot i2! in the arm HQ, and, at its other end is in cooperative relation with the cam section HBS on the lever arm |065. The bar |23 is provided on its end with a slot which engagesthe cam |08, so that as the lever, arm IM is rocked, the bar |23 is shifted laterally. In Figure 10 the bar |23 is in the position to set the machine in condition to perform probleme in division. When the machine is set to perform problems in multiplication, to the left by the cam member W6. Pthe bar |23 has a rather tortuous shape in the present machine, due to the necessity of avoiding the the machine, but the construction or function.

Pivoted to the stud @i5 (Fig. i6) is a lever |125 to which is pivoted the substantially vertical linii |26 (Fig. 10 and Fig. le) which at its lower end bears against the arm of the bell crank lever |27. The bell cranlr. lever is pivoted on the brach et |28 and the vertical arm |2 or the lever is forked and engages the collar lili secured: to the rocl 26. lire horizontal arm i277 oi the bell crank lever is thus held elevated by' the spring 4| associated with the rod 23 (Fig. l0). The lever 25 to which the bell crank lever is con-= nected by means ci the linlr i2@ is therefore normally held in its elevated position.

Means are provided for quickly depressing the lever |26 at the proper time in the operation of the machine, to shift the rod 28 to the left thus shifting the pin, 2l and causing the re= versai of rotation of the actuator. lllounted in the upper end ci the lever i2@ is a spring re strained pin i3@ which is normally in depressed position. 'This pin lies adjacent a cani it@ se cured to the actuator shaft and, when the pin is projected, it lies in the path oi the cam and is struck by the carri just before the actuator reaches full cycle position. When the cem strikes the projected pm, the lever M5 is rocked in counter-clockwise direction depressing `the link |26 and thus moving the rod 2S to the right (Fig. 10) shifting the reversing gear. During the operation of division, the actuator rotates in a reverse or ceunterclockwise direction and the cam 35 is so positioned that it operates to shift the rod 28 when the actuator is in full cycle position, thereby permitting the shifting of the the bar l2@ is moved itv ver iii which rocks in a plane at right angles,

to the plane of movement of the lever 22. The lever ist, at its upper end, engages in a groove in the pin i813 and at its lower end is provided with a foot 32 which lies below the plane of the rear end of the arm iis. When the machineis set for performing problems in addition. subtraction and multiplication, the arm il@ is rociredto one sida-ao that it does not overlie the foot i853, but when the machine is set for perfo :..zprobl in division. the arm il@ is movedi-to the position shown in Figure i0. where it over-lies the :Zoot i3d. upon the occasion or an overdraft registration or transitional carry, the lever il@ is rocked, depressing the arm iii) consequently rocking the lever il'l to project the pin idd into the path of the cam E35. At full cycle position, the cam i3@ strikes the pin i3d, rocks the lever i2@ and shifts the pin 2l of the reverse gear, to reverse the direction of rotation of the actuator. This is accomplished without disengaging the clutch.

Means are also provided for disengaging the clutch and stopping the actuator at the end of the first cycle of reverse or additive rotation.

Pivoted on the shaft' lidi (Fig. 1c) is a' lever i162 havingan arm idd which underlies the horizontal arm of the `V'bell crani: lever i2?. Therefore, when the horizontal arm of the bell crank lever is roclred by the cam iil, the lever i132 'is roclred in a countercloclswise direction. The arm M2 oi the lever which is raised when the lever is rocked underlies the end of the lever .i135 which is pivoted intermediate. its end and which is connected atits other end by the pin ifi@ (Fig. l0) with the lever lili which is provided on its end with a tongue id@ which is disposed in the aperture id@ formed in the clutch control bar lli. The levers M5 and lill are so arranged, that downward movement on the horizontal arm of the bell crank lever i2?! causes upward movement of the tongue i432, which kicks ver iii. by virtue of the overdraft registration' is so timed that the aperture i@ in the clutch housinghas moved pest the end i@ of theclutch control lever before such lever comes into contact with the clutch housing so that the clutch housing makes one complete revolution after the operation of the automatically operated re. verse mechanism. At the end of this one rotation, the foot l2 on the end of the clutch lever i9, engages in the aperture l@ and disengages the clutch and locks the clutch housing against rotation. 1t is seen therefore, thatas a result of the overdraft registration, that the direction of rotation of the actuator is reversed without causing disengagement of the clutch and that the rotation of the actuator is stopped at the end of the rst cycle of corrective rotation. This single cycle of corrective or additive rotation, corrects the. error in the quotient register and in the product register, caused by the overregistration which resulted in the transitional carry.

Means are provided for locking the positive operation lrey against movement when the ma- Conseouently, l

atrasos chine is set to perform problems in division, so that the positive operation key may not be inadvertently operated, which would result in the introduction of error into the machine. Means are alsoiprovided, when the machine is set to perform problems in division for holding the negative operation key in depressed position,

until the problem is completed, thereby eliminating the fatigue of the operator which is caused by the continuous holding down of the negative operation key. It has been shown, that positioning of the setting lever Qt in division position moves the bar E35 bacirwardi` thereby rocking the lever 62 (Fig. 8), the horizontal arm of which underlies the pin 56 on the stem of the negative operation key. Disposed within the machine in correlation with the horizontal arm of the lever 52 and the roller @il on the frame @i oi the pitive operation lrey` @i isla lever 962, one end oi whichl lies under the horizontal erm of the lever S2 and theA other end of which lies under the roller Gb. when kthe lever 52 is releasing the hey upon the completion or the problem in division. The solution of the problem in division involves successive operations of the actuator and successive shiftings of the carriage and the negative operation key is held depressed until the carriage reaches its extreme position of movement which position is determined by' the capacity of the machine. The stem of the negative operation key Si is provided adjacent its lower end with a notch 253i which is engaged by the spring pressed latch 282, when the key is depressed, to hold the hey in depressed position. Means are provided for holding the latch in inoperative position, when the machine is set to perform problems in addition, multiplication and subtraction, and for releasing the latch to operative position when the machine is set to perform problems in division. This means, which also serves, when the machine isv set to perform problems in division, to move the latch to release the negative operation key 5l when the problem in divisionhas been completed, after the carriage has reached its limit position at the left of the machine, will be described in full hereafter.

The present machine also embodies means for automatically shifting the carriage after the ordinal registration operation and tens carrying operation has been completed in the corrective forward rotation of the actuator, when performlng problems in division. The carriage is slid-A able transversely in the trackway il@ to which is secured the casing m2, within which is arranged the carriage shifting device. The carriage shifting mechanism employed is fully illustrated and described in `my copending application Serial Number 539,422 filed February 27, 1922 and issued as Patent No. 2,028,540, on January 21, i936, to which reference is hereby made for a complete disclosure of one form of carriage shifting means. These means comprise a slide having a stud isb (Fig. 11) which is engaged by the slotted shifting arm its. which is secured to the rod H92, jour- Z5 nailed in the frame |82 and extending to the front of the casing of the machine where it is provided with a lever or wheel whereby the rod |82 may be rocked in either direction to shift the carriage one step at a time in such direction. The present invention embodies power driven means which are automatically brought into operation at the end of the correcting cycle of rota.- tion of the actuator, to shift the carriage one step to the left, as shown in Figure 11.

Extending from the arm |93 above the rod |82, is a stud |38 which is engaged by the reciprocable link |91 which extends transversely of the machine. The link |81'is provided on its end remote from the shifting arm |33 with a notch |88 in which is disposed the periphery oi' the circular cam |99. The cam is so shaped, that one rotation thereof will cause reciprocation of the link |81 thereby rocking the arm |33 and shifting the carriage 5 one step to the left. Secured to the cam 09 is a clutch housing 20|, which is rotatably mounted on the shaft 202 which is driven by the motor. Secured to the main driving shaft 8 is a gear 203 which drives the shaft -204 thru the gears 20B and 208. Secured to the shaft 204 is another gear 201 which drives the gear 208 secured to the shaft 202, thru the idler gear 203. 'I'he shaft 202 is therefore driven when the motor is in operation. Secured to theshaft 202 is a clutch ratchet 2|2 which is adapted to be engaged by the clutch dog 2|3 (Fig. 7) which is pivoted to the clutch housing. The mode of operation of this clutch is identical with that of the clutch i3 and the position of the clutch dog 2I3 which controls the engagement and disengagement oi the clutch is controlled by the clutch lever 2|4 which normally extends thru an aperture in the periphery of the clutch housing 20|, to engage the clutch dog 2i3 and hold the clutch disengaged. The cam (Fig. 6) is normally heid in full cycle position by the clutch lever 2i4 and when in such position, a notch 2I5 in the cam lies in the plane of the link |91, so that the link may be moved transversely by hand when the carriage is shifted by operation of the manual shifting key.

Means are provided for controlling the operation of the clutch lever 2|4 to control the action of the clutch, and these controlling means are automatic and are preferably actuated upon the reverse or additive rotation of the actuator. The clutch control lever 2|4 is secured to the shaft 2i8 to which is also secured an arm 2| 1 (Fig. 3) which is normally held in position by the spring 2|8. In order not to confuse the drawing only a portion of the spring 2id is shown, but it is understood that it extends to the left and is secured at its other end to the frame of the machine. This spring holds the clutch control lever 2id in normal clutch disengaging position as shown in Figure ii. I

Means are provided for rocking the shaft 28B vto causeengagernent of the clutch and subsequent disengagement thereof at the end of one rotation by the reverse or additive rotation of the actuator. In performing problems in division, the' multiplier register drum 8| (Fig. 3) rotates initially in a clockwise direction, while the actuator is rotating in a subtractive direction. Upon the reversal of the direction of rotation of the actuator, the direction of rotation ot the drum 8| is reversed so that it now rotates in a counterclockwise direction. Secured to the drum 8i is a pin 22| and disposed between the path of the pin and the stud 222 on the end of the arm 2| 1 is a slide 223 which is normally heldin retracted position by the spring 224. The upper end of the slide 223 is bevelled at 225 and, the position of the slide, due to the action of the spring 224 is such that on subtractive or clockwise rotation of the drum 8|the pin 22| contacts with the bevelled end 228 and moves past the slide, the slide rocking on its pivot 228, to permit this action to occur. I'he slide is prevented from rocking in the opposite direction by contact thereof with the shaft 204. Rotation of the drum 8| in a reverse or counterclcckwise direction, as shown in Figure 3 brings the pin 22| into engagement with the hat end face 221 of the slide 223, forcing this slide downwardly against the pin 222 and rocking the lever 2|1 and consequently the clutch control lever 2|4 to disengage the clutch.

In Fig. 3, the drum 8| is shown in full cycle position. Due to the provision of sufficient backlash ln the gears and 86, the momentum of the rotating drum carries it past full cycle position, when the clutch housing I3 is stopped, and the movement past full cycle position is sufiicient to oscillate the slide 223 to release the clutch 20|. The spring 224 returns the drum 8| to full cycle position and the spring 2|8 returns the lever 2i4 into contact with theperiphery of the drum 20|, so that at the end of the cycle of rotation of the clutch housing 20|, the lever 2|4 drops into the aperture in the periphery thereof, disengages the clutch and stops the clutch housing. The pin 22| strikes the slide 223, after the ordinal registration and tens carrying registration has been completed so that the carriage is free to be shifted transversely. Thus, when the machine is set to perform problems in division, the initial cycle o additive rotation of the actuator not only operates to stop the rotation of the actuator at the end of the Cycle, but also operates to shift the carriage to its next position.

The invention contemplates the provision oi' means for disabling the automatic carriage shifting means, when the machine is employed in performing problems in addition, subtraction and multiplication. Projecting from the bar e8 (Fig. 3) adjacent its rear end, is a finger 229 which lies in a plane at one side of the slide 223. Projecting from the side of the slide 223 is a pin 236i under which is disposed a saddle 235 which is movable upwardly and whose function will hereinafter be described. The nger 229 lies in the plane of the saddle and when the lever @E is moved to its multiplication position, the inger contacts with and raises the saddle 235, thus rocking the slide 223 on its pivot to move the iower end thereof upward so that the pin 222 on the lever 26T does not now lie in the path of movement of the slide. Therefore, upon. additive rotation of the drum iii, the slide is reciprocated, but. since the pin 222 lies out oi the path of the slide, the reciprocation of the slide is ineffective insofar as shifting oi' the carriage is concerned.

it has been shown, that when the machine is set to perform problems in division, that the main driving clutch is disengaged and the clutch housing i3 brought to a stop at the end of the first cycle oi corrective or additive rotation of the actuator. The clutch is disengaged and stopped by the release of the clutch lever i8, and during the time that the main clutch is stopped, the carriage is shifted to the next position. The invention contemplates means for automatically reengaging the main clutch and releasing the clutch housing i3, after the carriage has shifted,

to continue the divisional operation in the next numerical position. This is accomplished by means of a cam 2M secured to the carriage shift#- ing clutch shaft 222. Cooperating with the lcam 268 is a lever 262 carrying on its end a roller 2623 which engages the cam. The lever 262 is securedto a rock shaft 22d, which is journalled in the frame of the maclune, and secured to the other Vend of the shaft 2M is a nager 265 which engages underneath the clutch control lever i2. The cam 243i is positioned so that it rocks the shaft 26d, as the shaft 222 reaches the end of its cycle of rotation. The rocking of the shaft 26d by the cam 26d, moves the finger 265 (Fig. 2) ina clockwise direc`= tion, thereby rocking the clutch lever is to cause engagement of the main clutch and the release of the clutch housing i3 so that the driving connection is 'again established between the motor and the actuator. The clutch control bar li is held in clutch disengaging position, by the latch 232 which holds the negative operation key 5i depressed and, when the clutch control lever i8 is rocked by the arm 213e, the pin i3 on the clutch control lever engages in the notch i12 in the end of the clutch control bar li, so that the clutch Y control lever is held out of engagement with the clutch housing i3. On the occasion of an overdraft registration, the clutch control bar lli is again kicked upward, as heretofore described, releasing the clutch control lever i2. The cam 2G i is of short circumferential dimension so that after theV arm 255 is moved to cause the release of the clutch housing il), the arm 256 moves back to inoperative position, so that it will not interfere lvith the subsequent movement of the clutch conmi lever se to clutch eisenganng positieh, upon the corrective or additive rotation of the actuator, following an overdraft registration. J a

Means are provided for terminating the operation of the machine, when it is set to perform problems in division, when the carriage has reached its furthermost position atV the left. The carriage trackway il@ is provided with an aperture 22S which is normally covered by the carriage, and which is uncovered when the oarriage reaches its furthest position in its movement toward the left. Pivoted to a bracket arranged belowthe trackway il@ is a trigger 2de which is normally held in restrained position against the action of the spring i by a latch 222 which is normally in engagement with the bracket 253. The trigger 249 is provided with' a finger 22d which projects into the aperture 222 and which is normally held from moving upward lby the base of the carriage E, which normally overlies the aperture. When the cai'-- riage moves to its left position. as shown in Figure 12, the trigger, when released by the latch, may move to project the finger 22d above the plane of the trackway ill?. The latch. 252 is provided on its side with a pin 23E which overlies the'automatic clutch tripping lever M2 and, when this lever is operated to trip the clutch, the latch 252 is raised .from engagement with the bracket 262. When, however, the aperture 262 is covered by the carriage, the trigger 2de A cannot swing about its pivot 25B and consequently, the latch 252 drops back into engage- "ment with the bracket 252, When, however, the

aperture 2d@ is uncovered, the release of the latch 252 permits'the spring 2m to rock the trigger 26s about its pivot 252 and this occurs during the rrective or additive rotation of the actuator, after the carriage has reached its limit pothe pin 241@ projecting from asientos are provided, which are thrown into operation by the movement of the trigger 2li@ forl bringing the machine to a stop. Fulcrumed on the pivot 2b@ of the latch 2l3 is an inclined lever 222 which, in combination with the similar lever 262 plvoted on the bracket 2ti, forms a pair of parallel levers. The other ends of the levers are pivoted to a swing member 222 by the pins 223 and 225. The latch 2de carries at its lower end a pin 222 which lies in contact with the inclined face or" the lever 258 and when the latch 262 is released and is moved by the spring 258 ina counterclockwise direction, the pin 222 swings the swing member 262 (Fig. l2) upward and to the right. The swing member 222 is provided with a foot 222, which underlies the finger 222 which comprises an extension of the latch 232 and. when the swing member 252 is swung by the trigger 26s, the finger 222 is lifted, causing the latch 222 to disengage the negative operation key ti. The upward movement of the key 5i permits the spring to draw the clutch control bar li backward, out'of cooperative relation with the pin 23 on the clutch control lever, so that the clutch remains locked and the machine is brought to a stop. a

The saddle 282 (Fis. 3) which underlies the pin 28d is formed on the .end of the swing member 222 (Fig. l2) so that as the swing member is moved upward, the saddle 235 is lifted, swingfil ing the control bar 222, so that its lower 7end is movedout of the path of the pin 222 .so that the carriage shifting mechanism is not thrown into operation. Therefore, the machine is brought to a stop after the corrective or additive rotation of the actuator, when the carriage ,is ir its limit position to the left. Since this circuit being normally open. The switch is closed by the depression of any of the operating keys and remains closed only during such time that the mechanism of the calculating machine is in operation to perform a calculation, to shift the carriage or to reset the registers of the calculating machine to zero. When the machine is set to perform problems in division, the motor switch is closed by the depression of the negative operation key 2i and remains closed until the depressed negative operation key is released by thc tripping of the latch 222. The motor circuit is provided with a switch 2id (Fig. 18) which is closed by hand by the operator when he desires to use the calculating machine. This switch, however, does not close the motor circuit, because such circuit is provided with another switch which must be closed before the circuit thru the motor is closed. The second switch is arranged to be closed upon depression of any of the control keys, and, since all of `these keys are associated with the clutch control lever is, the operating mechanism for the second switch is preferably associated with said lever is so that upon depression of any of the control keys, the control switch is closed. In the present construction, the control switch 2li (Fig. 2) comprises two metallic elements 2l@ and 2l@ spaced apart at their lower ends by suitable insulating material 28|, and suitably bound together by screws 282 which do not however contact with the metallic elements 218 and 219. The block of insulating material 28| in which the elements 218 Aand 218 are held, is mounted on a shaft 288 which is suitably journalled in the frame of the machine,`so that 'the insulating block 28| and the resilient metallic contact may be slightly rotated. The metallic elements 218 and 219 are provided at their upper ends with normally spaced contacts 284 and 285 and the metallic element 219 is in contact with an insulating stud 289. A slight rotation of the shaft 283 in a -clockwise direction (Fig. 2) causes the flexing of the metallic element 218,\due to its contact with the stud 286, bringing the two contact members 284 and 285 together and closing the circuit thru the motor. The member 219 possesses sufiicient resiliency to return the insulating block 28| to the position shown in Figure 2 upon the release of the pressure tending to rotate the shaft 283 so that a torsional strain is required to rotate the shaft 283 to bring the contact 284 and the contact 285 together, and when such torsional pressure is released, the switch opens. Secured to the shaft 283-is an arm 281 having a slot therein, in which is disposed the shouldered end of the link 288 which, at its forward end is pivoted to the lever 289. The lever 289 is provided at its upper end with a lateral extension 289e which lies behind the clutch control lever I8. Interposed between the clutch control lever and the extension 289a (Figs. 4 and 5) is a lever 290 which is normally in close contact at its upper end with the extension 289e and the rear end of the lever I8. Therefore, movement of the clutch control I8 in a direction to release the clutch housing and cause engagement of the clutch, rocks the lever 289 backwardly, thus rocking the shaft 283 and bringing the contact 284 and the contact 285 into engagement, closing the. circuit thru the motor. As longas any of the control keys is held depressed, the clutch` lever I8 is held in the position shown in Figure 4, holding the extension 289e pressed backward and holding the switch closed. In the operation of the machine, however, when it is set to perform problems in addition, multiplication and subtraction either key 5I or GI is frequently given an abrupt tap and is not held depressed and means are provided forl preventing the immediate reopening of the switch, when this practice is employed. It will be noted in Figure 4 that there is a material clearance between the end of the foot I9 on the lever I8 and the periphery of the clutch housing I3, and when pressure on the key is released, the foot I9 moves forward and rides on the periphery of the clutch housing as shown in Figure 5. This forward movement of the foot I9 and the consequent forward movement of the lever 290 would permit, if not prevented, a forward movement of the lever 289, which might be suilicient, either due to wear orthe lack of close adjustment, to open the motor circuit and cause the machine to stop with the actuator out of full cycle position or in mid cycle position. To overcome this possibility, I have associated the lever 289 with the full cycle stop means, so that the switch is always held closed during the time that the calculating mechanism is out of full cycle position. Associated with the clutch housing I3 is a full cycle stop means or centralizing lever 292 which is provided on its end witha cam projection 293 which normally seats in a cam notch 294 in the side wall of the clutch housing to position and hold the -housing and consequently the actuator in full cycle position. The cam projection 293 is pressed into the notch 294 or against the periphery of the housing by the strong spring 295,- which is of sumcient strength to position the housing in full cycle position. Upon the initial movement of the clutch housing from full cycle position, the centralizing lever is moved counterclockwlse bringing the upper end thereof into contact with the backwardly pressed arm 289e of the lever 289 as shown in FigureA 5, and holding such lever in switch closing position until the clutch housing again reaches full cycle position. The arrangement of the switch operating parts is preferably such that tbe contacts 284 and .285 are brought together starting the motor before the pawl I4 engages the ratchet I2, thereby permitting the motor to gain speed before the load is applied thereto.

When themachine is set to perform problems in division, the main driving clutch is disengaged during the time that the carriage is being shifted and means are provided for preventing the opening of the control switch 211 during such time. The shaft 283 on which the switch is mounted, is provided at its end with a rightangled extension 291 (Fig. 6) which is moved upwardly when the Switch is closed.' Pivoted on va bracketV 298 is a lever`298 having an eye (Fig. 17) at its end, which surrounds the extension 291. The other end of the lever 299 extends forwardly and is provided on its forward end with a foot 302. Disposed in cooperative relation with the foot 302 is an arm 303 which is secured to the rockshaft 304. Secured to the rock shaft 304 is an arm 305 which is provided on its end with a shoe 306 which is in operative engagement with a cam`301 secured to the shaft 202. The cam 301 is so designed and so placed, that it raises the shoe 306 and consequently depresses the foot 302, holding the extension 291 elevated, during the time that the centralizing lever 292 is in engagement with the notch 294 in the side wall of the main clutch. Therefore, during the time that the main driving clutch is disengaged and the clutch housing held stationary, the motor switch is held closed so that the motor drives the carriage shifting mechanism. Upon the conclusion of the operation of the carriage shifting mechanism, the clutch control lever I8 is again moved to free the clutch housing and, during the time that the clutch control lever is in, this position, the switch is held closed by such lever. When the machine is brought toa stop, after the carriage has reached its limit left hand position, the main driving clutch is disengaged and the carriage shifting control bar 223 is moved to inoperative position, so that the carriage shifting means is not operated. Therefore, the shaft 202 is 'not rotated and consequently the mechanism for holding the switch closed is not operated, so that the switch is opened and the machine brought to a stop.

I have therefore provided in a calculating machine, means for setting the machine to perform problems in division, which means function to correct the overdraft registrations in the respective numeral orders, to alternately shift the carriage, that is between divisional operations to the next numeral order, to maintain the electric circuit of the motor closed during the time that 

